I had a trip up to Dunstanburgh Castle, in Northumberland at the weekend with Alan. It’s a while since I’ve been up there, last time was in the winter, through sheet ice and my 450D locked up after I’d taken one shot on the way to the castle. I was hoping to fare better this time, though it was late morning, in glorious sunshine and there was virtually no cloud – generally not a good time to shoot.

We ambled up to and around the castle, took a few shots, but I hadn’t found a stand-out image. I’d taken filters along, and used a polariser and an ND8 hard gradient to no avail, the images just didn’t sing – they were nice, mind, but not much atmosphere.

Around the back of the castle we found a lake had formed, with a bit of fence sticking out of the middle of it. It was possible to get the tower of the castle in too for a nice composition, but the sun was just above the castle, and the netural density filter was struggling to do much about it.

Then I remembered – as I’d grabbed my entire collection of four filters, and stuck them in a pouch, that meant I’d have an infra-red filter in there somewhere. Infra-red filters look like they’re black, though if you look at the sun through them, they’re a very deep red. The block out most of the visible spectrum but all the wavelengths around the IR end through. At least that’s how my brain figures it, there may be a better technical explanation. Because most of the light is kept out, exposure times are around the 30 second mark, so a tripod is essential. So what do you get? Well, if you’re shooting in colour, you get a picture that looks like you had a red filter over it, but when you convert it to black and white, you get some amazing contrast, some very sharp shadows and foliage that’s white or very light. Remarkable skies, too, if there’s a bit of cloud there, as the blue turns black and the white (backlit by the sun) stays bright.

It’s also the only way I’ve found to get a long exposure during the day – shooting rivers or waves, for example.

Anyhow, my lesson from the trip out is: if you buy kit and leave it at home, you won’t get much use out of it. Pretty much the reason why I got a light tripod a few years back – the one I had was fine, but I never took it anywhere because of the weight – so it rarely got used.